Arresting means for moving objects



May 15, 1962 c. J. DANIELS ARRESTINO MEANS FOR MOVING OBJECTS 2Sheets-Sheet l Filed Feb. 26, 1960 .ATTORNEY May 15, 1962 c. J. DANlELsARRESTING MEANS FOR MOVING OBJECTS 2 Sheets-Sheet 2 Filed Feb. 26, 1960ATTORNEY United States Patent C) 3,034,749 ARRESTING IVIEANS FR MGi/MGOBIECTS Charles l. Daniels, Wilmington, Del., assignor to All AmericanEngineering Company, Wilmington, Del., a corporation oit' Delaware FiledFeb. 26, 1960, Ser. No. 11,247 2 (Jiaims. (Cl. 244-110) This inventionrelates to means for decelerating moving objects and is acontinuation-impart of my co-pending application Serial No. 602,860, ledAugust 8, 1956, now abandoned and assigned to the assignee of thepresent invention.

The invention is more particularly concerned with object arresting meanscharacterized by an elongated tube having a lluid therein, together witha trailing elongated exible member, such as a cable movable axially ofthe tube under action of a moving object and wherein a motion arrestingforce is provided by a skin friction between the cable and fluid uponrelative movement thereof, in the tube.

A primary object of the invention is the provision of an elongated tubehaving a fluid therein together with a trailing cable movably disposedwithin the tube, and wherein the tube is of variable diameter forvariable reaction between the fluid and the surface of the cable withcorresponding resistance to movement of the cable through the tube aseected by skin friction between the fluid and the cable.

A further object of the invention is the provision of an elongated tubehaving a fluid therein, including a cable section connected to an arrestcable, and a trailing cable connected to said arrest cable connectingsection movably disposed within the tube, and wherein the trailing cableis of a relatively larger diameter than said arrest cable connectingsection for a variable reaction between the -uid and the trailing cablethrough the tube as effected by skin friction between the fluid and thetrailing cable.

A still further object of the invention is the provision of structure asset forth immediatelyl above, wherein the tube is also of variablediameter.

Other objects and advantages of the invention will become apparent inthe course of the following detailed description taken in connectionwith the accompanying drawings, wherein:

FIGURE 1 is a foreshortened vertical sectional view showing the generallayout of a tube or conduit arrangement on one side of a runway.

FIGURE 2 is a schematic top plan view of the arrangement in FIGURE l.

FIGURE 3 is an enlarged vertical sectional view of the tube structure ofFIGURE 1 at the arresting end thereof.

FIGURE 4 is an enlarged vertical sectional view of the tube structure ata joint between adjacent ends of a pair of tubes of different diametersand further showing a section of the arresting cable as it leads from arelatively large diameter of the last section of the arrest tube withrespect to the leading arrest tube sections.

FIGURES 5 to 7, inclusive, are vertical longitudinal sectional views ofdifferent forms or tube sections for operative embodiment in the layoutof FIGURE l and disclosing different methods of operation of theinvention.

Referring now in detail to the drawings, and first to FIGURES 1 to 4thereof, a conduit lil is disposed at each side of a runway R only oneof which conduits is shown to conserve space. The conduit lil comprisesa plurality of sections of diierent diameters. As shown,

.e conduit embodies tube sections ll and l2 respectively, disposed atthe arrest and retrieve or forward end rearward ends of the arrestconduit sections and which for the purpose of the present invention maybe for example six inches in diameter. Since the complete conduit `ltiis preferably disposed underground as shown, the tube sections il andllZ are inclined downwardly from foundations 13 and 14 on which theouter ends of the tube sections ll and l2. are supported.

A second tube section ill is horizontally disposed underground and oneend thereof is connected to the adjacent end of section 1l by means of aflanged coupling lia. The opposite end of tube section ll' is connectedto one end of a horizontal tube section 15, which may be for example, ofeight inches diameter as by means of a reduction coupling lo. Theopposite end of tube section l5 is -by means of a similar reductioncoupling 1.6 connected to one end of a relatively larger tube section17, which may be, for example, ten inches in diameter and the oppositeend of the tube section 17 is connected by reduction coupling il to theadjacent end of the relatively smaller inclined tube section i2. A cable19 extends through the conduit l@ and includes an elongated relativelylarger section 20 for a purpose later to appear.

The conduit 10 in accordance with the principles of the presentinvention is adapted to be filled with iluid, preferably water or waterand anti-freeze solution, and, accordingly, the several connectionsbetween the tube sections are uid-tight.

One of the joints as between tube section 17 and reduction coupling 18is shown in detail in FIGURE 4 and wherein it will be seen that a flange13a on the coupling 13 opposes a flange 17a at the adjacent end of tubesection 17 and which is welded thereto as indicated at 21. The anges*17a and 13a have a fiuid-tight contact as at 22 at which point a gasketmay be disposed and the anges are drawn into operative contact by meansof bolts 23.

The remaining joints between adjacent tube sections are preferablylikewise constructed.

The arresting or forward end of the conduit lil is provided with aspecial-connector for providing for smooth uninterrupted movement of thecable 19 from the inclined tube section lli to a horizontal position,that is to prevent cable kinking. Such connector is shown in detail inFIGURE 3, and which comprises a tube 25 of generally ogee form in theprovision of a dip section whose one end is connected to the adjacentend of the tube section `l1 by cooperating flanges 26 and 27 secured tothe tube section 111 and tube 25, as by welding 28. The anges 26 and 27are drawn into contact by bolts 29, similarly to the flange and boltstructure in FIG- URE 4. The opposite end of the tube 2S has weldedthereto a flange 3@ to which is secured by bolts as at 3l, a cap plate32. The cap plate 32 is provided with a relatively large axial bore 33in which is disposed a split bushing 34 having a ange 35 secured to thecap plate as by bolts 36.

As is clearly shown in FIGURE 3, the bushing 34 is provided with a bore37 whose wall is axially convex, thereby providing for smooth transitionof the cable `19 from the tube 25. A fluid supply line 39 ernanates fromany suitable source and the line communicates with the conduit 10through a suitable supply valve 40.

The conduit 10 is further provided with a sump 41, with which isoperatively associated a fluid level indicator 42. As indicated inFIGURE l the valve 4i] and sump 41 are preferably associated with tubesection 11 while the largest tube section 18 is provided with a U-shapedvent means 43.

The diagrammatic view in FIGURE 2 shows the conduit at one side of therunway K and wherein it will be seen that the cable 19 at the retrievingend of the conduit or energy absorber 10 passes over a fairlead sheave44 and forms into a loop 45. At the arresting end of the conduit 10, thecable 19 extends over a sheave 48 and may be connected as at 49 toadjacent ends of deck pendants 50 whose opposite ends are similarlyconnected to a corresponding cable at the opposite side of the runway,or the cable 19 may extend in either dot-and-dash line direction forengaging objects to be delivered or picked up, by a plane traveling inthe directions indicated by the respective arrows.

The energy absorbing capacity of the conduit 10 and cable 19 movablydisposed therein is effected by the interaction between the cable 19including the elongated member 20 and the. fluid in the conduit, thatis, skin friction, and the arresting capacity of such friction isdependent upon the surface area of the cable, its associated member 20and the relative rate of movement between the same and the surroundingiluid. The member 20 comprises another exible body, such as a cable ofrelatively larger diameter than cable 19 said member having sections a,b, c, d and e, which may be cut-off as required for drag adjustments bythe installation engineer.

For a better understanding of the energy absorbing principle as eifectedby friction between a body of uid and a cable movable therein, referencewill now be had to diagrammatic FIGURES to 7 in which are respectivelydisclosed different tube and cable structures, any of which may beembodied in the conduit and cable construction of FIGURE l.

According to FIGURE 5, the tube 61 includes an end section `62 of arelatively large diameter and an opposite end section 63 of relativelysmall diameter providing a radial shoulder 64 intermediate the ends ofthe tube. The tube 61 is provided in its opposite ends with bushings 65and 66; and the arresting cable S7 extends through the bushing 66 and isconnected with a relatively larger cable 67 whose advance end extendsthrough the bushing 65.

During arrestment the large cable 67 is drawn into the tube 61 and itssurface, which is substantially greater than the surface of arrestingcable 57, reacts with the fluid in the tube to provide skin friction,thereby tending to increase the tension in the larresting cable. Thelarger drag cable 67 may enter the reduced section 63 of the tube,wherein the clearance between the tube and the cable is such as tointerfere with the natural formation of the skin friction principle,thereby further increasing the drag on the arresting cable. Control ofthe arresting cable tension is attained by the selection of the propertube step-dovm, tube length and size of the cable. The tube ispreferably provided with a reservoir 68 having a pressure relief valve69.

According to the embodiment of FIGURE 6, the tube 70 is of the samegeneral form as tube 61 including the sections 62 and 63 and the radialshoulder 64. This ernbodiment also includes the arresting cable 57 andthe larger diameter cable 67. In this embodiment, however, the largerdiameter tube section 62 is provided with an accumulator 71. Inoperation, retracting movement of the cable 57 draws this larger cable67 through the tube and as the end of the larger cable approaches thesmaller end of the tube, fluid F will be caused to flow from the smallersection 63 in opposition to the movement of the arresting cable and intothe accumulator 71. The relative Velocity of the fluid past the cable 67is thereby increased with a resulting higher skin friction drag on thearresting cable 57. Control is attained by selection of proper cablesize and length, and tube sizes. For example, the diameter and length ofthe drag cable section 67 may be regulated by the installer of thismachine as in the rst embodiment, see FIGURE 4.

According to the embodiment of FIGURE 7 the tube includes a majorsection 72 and a minor section 73 whose common axis is inclined to thehorizontal with the major section lowermost and the minor sectionuppermost, and wherein a radial shoulder 74 exists at the adjacent endsof the sections. In this form, the arresting cable similarly to FIGURES7 and 8 is attached to a flexible arrest member of a relatively largerdiameter, such as the cable 67. Both ends of the tube are sealed as bybushings 75 and 76 and the tube is filled with fluid to a normal levelbelow the junction of the two tube sections 72 and 73. With thisconstruction, as arrestment progresses the larger cable 67 is pulledforwardly with a resulting displacement of fluid and causing same toflow back into the unfilled part of the tube. This increases therelative velocity of the fluid with respect to the larger elongatedexible arrest member or cable 67 and accordingly also increases the skinfriction drag on the arresting cable S7 connected thereto. Control isattained upon selection of proper tube dimensions, arrest cable and dragcable dimensions and fluid level.

Without further description it is believed that the present invention isclearly understandable to others authorized to practice the same. Whileonly a few embodiments of the invention described and illustrated indetail, it is to be expressly understood that other combinations,modifications and arrangements of the parts which will now probablyoccur to others skilled in the art are to be considered a part hereof.To determine the scope of the present invention, reference should be hadto the appended claims.

What I claim is:

1. Means for `arresting the forward motion of an object including a deckpendant, said means comprising an elongated conduit having a retrieveend and an arrest end filled with liquid, said conduit comprising aplurality of tubes coupled together in axial alignment, each of saidrespective tubes having a progressively different internal diameter fromthe next adjacent axial aligned tube, reduction coupling means forconnecting said different tubes in axial aligned end to end relation inthe provision of a plurality of progressively stepped-down bore sectionsfrom the said retrieve end to the said arrest end, an arrest cableextending through said stepped-down tube bores and a relatively largertrailing cable connected to said arrest cable to provide an arrestingmeans, operatively associated with said cable comprising `a relativelylarge elongated cable, said relatively large elongated cable havingseverable sections, said arrest cable with said relatively largertrailing cable being connected to said deck pendant positioned to beengaged by an object to be arrested.

2. Means for decelerating a moving object on a runway surface comprisingan elongated conduit having an arrest end and a retrieve end, a fluid insaid conduit, said conduit being installed below said surface, and acable extending across the runway and having an elongated enlargedtrailing portion extending through said conduit and extending out of theretrieve end of the conduit, said conduit comprising a plurality ofaxially aligned tubes each having an internal bore of a differentprogressively tapering size from the other tubes, reduction couplermeans for coupling ysaid tubes together, said cable with said enlargedportion being movable in the respective difww' v Y' References Cited inthe le of this patent UNITED STATES PATENTS Myer June 16, 1903 ord May1, 1956 Cotton Jan. 15, 1957 Ballard et al Oct. 25, 1960 FOREGN PATENTSGreat Britain Nov. 28, 1951

